Identifying the production region of single-malt Scotch whiskies using optical spectroscopy and pattern recognition techniques

The experimental study presented shows how optical spectroscopy can be used innovatively as a rapid and non-destructive tool for differentiating distinctive single-malt Scotch whiskies with respect to commercial-grade blends, and for classifying them according to the region of production. During the study, absorption and fluorescence spectroscopies are carried out without any sample treatment or handling. Spectroscopic data have been processed by means of multivariate analysis in order to design a discriminating map. The map shows that the cluster representing the single-malt whiskies from selected Scottish distilleries distinctly separates from the cluster of the commercial-grade blended whiskies. Moreover, the cluster of single-malt whisky is split into two subgroups, which represent samples from two main macro-areas: the “islands” and the “highlands”, respectively.